High shear thin film machine for dispersion and simultaneous orientation-distribution of nanoparticles within polymer matrix

ABSTRACT

An improved a device and method for dispersion and simultaneous orientation of nanoparticles within a matrix is provided. A mixer having a shaft and a stator is provided. The shaft may have a rupture region and erosion region. Further, an orienter having an angled stationary plate and a moving plate are provided. The nanoparticles and the matrix are fed into the mixer. A rotational force is applied to the shaft to produce shearing forces. The shearing forces disperse and exfoliate the nanoparticles within the matrix. The dispersed mixture is outputted onto the moving plate. The moving plate is forced across the angled stationary plate to produce fully developed laminar shear flow. The fully developed laminar shear flow or the two-dimensional extensional drag flow orients the dispersed nanoparticles-matrix mixture.

FIELD OF THE DISCLOSURE

The present disclosure relates generally to improved nanocomposites.More particularly, but not exclusively, the disclosure relates to thesimultaneous dispersion and orientation of nanoparticles within apolymer matrix during fabrication of polymer nanocomposites.

BACKGROUND OF THE DISCLOSURE

The use of composite materials is commonplace in today's manufacturingindustry. Composite materials advantageously display certain desiredphysical and/or chemical properties different from the constituentmaterials. Recent advances in materials science have includeddevelopment of polymer nanocomposites (PNCs). In the broadest sense,PNCs are comprised of a polymer matrix reinforced with nanoparticleshaving dimensions less than one hundred nanometers, but often in therange of one to fifty nanometers.

PNCs differ from conventional composite materials due to, among otherfeatures, a high surface area to volume ratio between the polymer andthe nanoparticles. For example, the total surface area in a unit volumeincreases 1,000,000 times when the particle size is decreased from onemillimeter to one nanometer. As a result, a relatively small amount ofnanoscale reinforcement can have an observable effect on the macroscaleproperties of the composite. In other words, the nanocomposite (NC)properties are drastically increased at low concentrations ofnanoparticles (NPs), generally 0.5-5.0 percentage by weight (wt %). Forexample, Young's modulus and yield strength are doubled at 1 wt % NPs incarbon nanotube/epoxy NCs compared to neat epoxy. One of the mostimportant properties affecting NCs characteristics is maximalinterfacial stress transfer between the polymer matrix and the NPsurface. This characteristic is strongly dependent on the degree ofdispersion and orientation of the NPs in the polymer matrix.

Incorporation of high aspect ratio nanoparticles (HARNPs), ornanoparticles with an aspect ratio greater than 100, into a polymermatrix can significantly increase mechanical properties such as elasticmodulus and tensile strength. Additional enhanced properties may includegas permeability, fire retardancy, transparency, and electrical andthermal conductivity, magnetism, shape recovery, wear resistance,corrosion resistance, permeation resistance, self-healing,anti-lighting, conductance, photoluminescence and electroluminescence.For example, carbon nanotubes (CNTs) improve the electrical and thermalconductivity of the composite. Due to such extraordinary and desirableimprovement in the properties of such composites, PNCs are used indemanding applications such as aerospace, automotive, electronics,computer technologies, and the like.

When properly dispersed, HARNPs (e.g., nanometer-thin platelets, such asclays to and graphene sheets, or nanometer-diameter cylinders, such asCNTs) interact with relatively more of a polymer chain than lower aspectratio NPs in a unit volume of NCs. By contrast, low aspect ratio NPs(e.g., nanorods, polyhedral oligomeric silsesquioxanes (POSS), silicaspheres) have fewer surface interactions to break, resulting in poorerperforming systems. Therefore, higher energy is required to breakHARNP-PNCs systems than low aspect ratio NP-PNCs systems. The nanosphererepresents a low aspect ratio NP while the nanoplatelet is a high aspectratio NP. Expanded polymer chains interacts with the HARNPs with muchfewer larger polymer chains than the low aspect ratio NPs.

Agglomeration of HARNPs reduces the effective aspect ratio of thenanoparticles and available surface for interaction. For example, theaspect ratio of an agglomeration containing 100 nanoplatelets is 1 whilefor a single nanoplatelet is 100. Further, the total surface area of theindividual platelet system may be increased by 34 times over that of theagglomeration. The increased surface area produces a significantincrease in platelet-polymer interactions, resulting in improvedperformance with only a small percent of NP addition. Therefore,obtaining complete dispersion becomes important in maximizing PNCperformance.

The polymer matrix and nanoparticles need to favorably interact witheach other at their interface, which plays a crucial role for mechanicalproperties. A central issue is that most polymer matrices and NPs arenot compatible with each other. In order to facilitate compatibility,NPs need to be functionalized with surfactants that are compatible withboth the NP and polymer matrix. The functionalization with surfactants,however, can have disadvantageous environmental impacts.

In general, there are four critical requirements for effectivenanoparticle reinforcement of NC materials: 1) high aspect ratio of NPs,2) interfacial compatibility between NPs and polymer matrix, 3) completeuniform dispersion, and 4) controlled orientation. As previouslydiscussed, higher aspect ratio NPs exhibit the best reinforcementeffect. Interfacial compatibility is vital to achieve effective loadtransfer between the NPs and the polymer matrix. For example, HARNP andthe polymer matrix need to be compatible with each other in terms ofsurface wettability. Complete uniform dispersion of NPs results inhigher surface area and a greater aspect ratio. Orientation of theHARNPs is critically important to enhance mechanical properties such astensile modulus and strength compared to the mechanical propertiesobtained from NCs with only dispersion. Additionally, orientation canresult in new and controllable anisotropic mechanical and functionalproperties in PNCs.

Properties of NCs are significantly affected by the fabrication method.For example, PNCs are commonly fabricated using melt mixing and solutionmixing methods. The melt mixing methods are attractive due to beingenvironmentally friendly, inexpensive, and continuous, but these methodslack the ability to disperse or orientate NPs, thus requiring the needfor additional processing. The solution mixing methods are discontinuousand environmentally unfriendly. Examples of the melt and solution mixingmethods include single and twin-screw extruders, two and three rollmilling, ultrasonication mixing, solution mixing, water injected meltmixing, high shear mixing, in-situ polymerization, melt dispersion,batch mixing, and mechanical stirring. However, these fabricationmethods have not been able to achieve NCs with the extent oftheoretically predicted superior properties due to inadequate dispersionof agglomerated NPs as well as inadequate orientation of the NPs in theNC.

The two-roll mill is not suitable for production at industrial scale dueto its difficulty to scale up and continuously processing withthermoplastic NCs. Single-screw extruders cannot provide sufficientdispersion in nanoscale even at low concentrations of weight percent ofNPs, because of its low shear rate. Despite literature indicating thattwin-screw extruders are the best dispersing machines among melt mixingtechniques, the twin-screw extruders can only partially exfoliate oronly disperse nanoparticles within polymer matrix. The twin-screwextruder is extensively used for mixing. Thus, the single screw extruderis not an efficient dispersive mixer because of insufficient high shearregions. In a single screw extruder the high shear region is createdonly within screw flight clearance. For instance, in a single flightedsingle screw extruder rotating at 100 revolutions per minute, 65.4% ofmolten PNC does not pass over the flight, 27.7% passes once, 5.9% twice,and 0.8% three times. However, to achieve properly dispersed NCs, themolten PNCs should encounter at least twenty passes through high shearzones.

PNCs have been fabricated mainly by melt mixing, in-situ polymerization,solution mixing, and ultrasonication, depending on polymer and NPsproperties. The critical polymer properties included polymer solubility,viscosity of molten polymer, and polymer type such as thermoplastic orthermoset. In-situ and ultrasonication dispersion methods are notdesirable from an environmental point of view. Melt mixing does notrequire an additional processing step, its simplicity to facilitatelarge scale production for commercial applications, and it isenvironmentally friendly by not requiring a solvent. Melt mixingdispersion levels are lower than those obtained through ultrasonicationand in-situ polymerization because of the insufficient shear rate.Nevertheless, as mentioned earlier, these methods cannot work with highviscosity molten polymers. The NCs that are fabricated by currentmethods have not exhibited the extraordinary mechanical and conductiveproperties due to poor dispersion of the NPs.

During a typical melt mixing operation, dispersion occurs whenhydrodynamic shear forces overcome the cohesion forces between the NPs.The cohesive force could be comprised of Van der Waals forces,electrostatic forces, and/or magnetic forces. However, the hydrodynamicshear force is only suitable for dispersion of NPs agglomerations whenviscosity is high.

There are two types of agglomeration breakup mechanisms: rupture anderosion. The rupture mechanism occurs by splitting of the agglomerationinto fewer numbers of aggregates. The rupture process requiresrelatively high shear forces, the hydrodynamic force needs to be atleast five times higher than the cohesive force of the NPs. The particleerosion process is characterized by a continuous peeling of primaryparticles from the outer agglomerate surface. The particle erosionprocess occurs at lower hydrodynamic shear forces of two times thecohesive force depending on agglomerate behavior.

In order to achieve the predicted extraordinary mechanical andfunctional properties of PNC materials, the nanomaterials should beexfoliated, dispersed, and oriented within the polymer matrix duringprocessing. Dispersion and orientation of nanomaterials within thepolymer matrix can generally only occur after exfoliation of the HARNPs.Effective dispersion of the nanoparticles within the matrix is essentialto ensure consistent and predictable properties throughout thecomposite. Therefore, a need exists in the art for a system that iscapable of simultaneous dispersion and orientation of nanoparticleswithin a polymer matrix at high temperatures without solvents.

Dispersion of NPs within the polymer matrix is a complicated processbecause of the high viscosity of polymers, interfacial surfaceincompatibility between polymer matrix and NPs, and NP agglomeration.The high viscosities of molten polymers result in laminar creeping flowsin PNCs processing. And if turbulent flow is created polymer degradationwill occur due to viscous dissipative heating and the difficulty inremoving the heat from the system. On the other hand, the high viscosityof molten polymer enables greater transfer of the shearing forces to theagglomeration.

Furthermore, controlling placement (i.e., orientation) of the dispersedNPs can be obtained only after proper dispersion. Such orientationmethods commonly known in the art include shearing drawing, melt andelectrospinning, equal channel angular extrusion, drawing, filtrating,applying magnetic and electric field, shear flow, spin coating,gas-liquid interfacial flow. However, none of these methods haveproduced a NC with properties close to the theoretical mechanical andfunctional property limits. For example, the drawing and the variousspinning methods produce only one-dimensional materials such as fibers.Other methods such as electric and magnetic fields and shear floworientation methods can produce two dimensional films or threedimensional bulk NCs; however, these fabrication methods have not yetreached practical usage. The shearing orientation method is the mostpromising method when compared with aforementioned orientation methodsbecause it does not require special functional properties of the NPs.For example, a key factor for shear orientation is the high aspect ratioof the NPs while electrical and magnetic field orientations requireanisotropic electrical and magnetic properties of the NPs, respectively.

Orientation does not require high energy as is necessary for dispersion.However, orienting HARNPs within a polymer matrix requiresfully-developed, steady, laminar, shear flow (FDSLSF). Achieving FDSLSFis complicated due to surface roughness at the nanoscale. Therefore, afurther need exists in the art for a system that is capable ofgenerating FDSLSF to orient the PNCs.

A high degree of orientation and distribution of dispersed HARNPsthroughout the matrix can give the greatest strength and stiffness alonglong axial direction, but the material is much weaker in the otherdirections. If the HARNPs are randomly oriented (i.e., isotropic) themechanical and physical properties will be intermediate. Easier transferof electrical and thermal energy will occurred along oriented directionof HARNPs when all HARNPs are oriented in same direction within polymermatrix. Achieving consistent uniform dispersion, alignment, andorientation of the HARNPs will allow optimal property improvement.Controlling the alignment and orientation of HARNPs in the polymermatrix can be tailored to best fit the NCs desired application.

It has been established that HARNPs are orientated along shearingdirection in shear-induced flow because of the HARNPs anisotropicphysical structure. Anisotropic properties of HARNP PNCs displayed verysubstantial physical effects in barrier, mechanical, and electricalproperties. Generally, polymer nanoclay NCs show dramatic improvementsof their barrier properties due to their tortuous gas diffusivity paths,known as Nielsen's theory. The barrier properties are enhanced when theexfoliated clay platelets are oriented. The oriented NCs have longertortuous paths than randomly dispersed NCs.

The NC with oriented CNT always shows higher reinforcement along theoriented direction of the CNTs than randomly dispersed. Orientation ofthe HARNPs within polymer matrix exhibits enhanced tensile modulus andstrength properties than the only dispersed HARNPs within polymermatrix. Similarly, it has been demonstrated that CNTs can dramaticallyenhance the electrical and thermal conductivities of polymers. Theelectrical and thermal conductivities along oriented direction aresignificantly higher than other directions.

Additionally, polymer chains are extended during the shear-inducedorientation. Polymers with extended chains have denser packing thanfolded chains. Furthermore, the polymer crystallinity is increased dueto polymer chain extension. Therefore, revolutionary progress in CNTapplication can only be realized when a technique is developed for thedispersion of the entangled CNTs and then controlling the dispersed CNTsorientation within the PNCs. The improved crystallinity leads to highstrength, good toughness, high stiffness, low gas permeability, a highermelting point, good fatigue life, good abrasion resistance, and enhancedchemical resistance.

SUMMARY OF THE DISCLOSURE

It is therefore a primary object, feature, and/or advantage of thepresent disclosure to improve on or overcome the deficiencies in theart.

It is another object, feature, and/or advantage of the presentdisclosure to simultaneously achieve high degree of dispersion andorientation of HARNPs within a polymer matrix. The high shear thin filmmachine (HSTFM) can work with any viscous medium such as moltenthermoplastics, liquid thermosets, and oil, because the higher viscosityenables greater transfer of the shearing forces to the agglomeration.

It is yet another object, feature, and/or advantage of the presentdisclosure to provide for an environmentally conscious and safe processthat does not require solvents. The processed part fabrication time isshort compared to techniques which use solvents because the HSTFMprocess does not require time to add and remove solvents from thepolymer-NP mixture.

It is still yet another object, feature, and/or advantage of the presentdisclosure to continuously process HARNPs within polymer matrix. Thecontinuous process makes the operating cost lower compared todiscontinuous mixing techniques. Also, productivity of the HSTFM ishigher than discontinuous processing such as batch processing. The HSTFMcan produce high degree of dispersion and orientation of BARNP withinpolymer matrix within a continuous process.

It is another object, feature, and/or advantage of the presentdisclosure to reduce processing time. The HSTFM processes the HARNPs inapproximately twenty seconds, including a dispersing time of ten secondsand orientation time of approximately ten seconds. The dispersing timeis remarkably short in comparison with twin-screw extruder, batchmixing, and ultrasonication, whose dispersing times are approximatelythree minutes, ten minutes, and twenty minutes to several days,respectively.

It is yet another object, feature, and/or advantage of the presentdisclosure to increase polymer crystallinity during the orientation ofthe HARNPs within a molten polymer. Increasing the polymer crystallinityis caused by orientation of polymer chains in the HSTFM orienter. Theincreased polymer crystallinity increases mechanical and opticalproperties of the polymer.

It is still yet another object, feature, and/or advantage of the presentdisclosure to provide for a stable product after processing because thedispersed and orientated HARNP NC melt immediately solidified afterprocessing. Thus, the HSTFM prevent reagglomeration of dispersed HARNPswithin polymer matrix.

It is another object, feature, and/or advantage of the presentdisclosure to produce larger effective applied shear energy region ofshaft.

It is yet another object, feature, and/or advantage of the presentdisclosure to provide for a self-cleaning heterogeneous catalyst reactorwhen the inside surface of stator and outside surface of shaft mixingregion are coated by a catalyst. One challenge of current heterogeneouscatalyst reactors is fouling of the catalysts over period of time. Thisissue could be solved when using the HSTFM mixer as heterogeneousreactor because the high shear rate which occurs within the HSTFM mixerwill protect the catalysts surface from fouling.

It is still yet another object, feature, and/or advantage of the presentdisclosure to increase the types of NPs and polymer matrices fororientation. The requirement for HSTFM orientation requires only viscousliquid and high aspect ratio NPs. By contrast, electric fieldorientation requires anisotropic electrical properties from NPs whilemagnetic field orientation requires anisotropic magnetic properties fromthe NPs. Therefore the HSTFM orienter can find more general applicationthan electrical and magnetic orientation methods.

It is another object, feature, and/or advantage of the presentdisclosure to control the temperature in mixing region and minimizeviscous heat degradation.

These and/or other objects, features, and advantages of the presentdisclosure will be apparent to those skilled in the art. The presentdisclosure is not to be limited to or by these objects, features andadvantages. No single embodiment need provide each and every object,feature, or advantage.

According to an aspect of the disclosure, a method for dispersion andsimultaneous orientation of nanoparticles within a matrix is provided. Amixer having a shaft and a stator is provided. Further, an orienterhaving an angled stationary plate and a moving plate are provided. Thenanoparticles and the matrix are fed into the mixer. A rotational forceis applied to the shaft. Shearing forces disperse the nanoparticleswithin the matrix. The dispersed mixture is outputted onto the movingplate. The moving plate is forced across the angled stationary plate.Fully developed laminar shear flow orients the dispersed mixture.

According to another an aspect of the disclosure, a device to disperseparticles within a matrix includes a housing having a center axis, anouter surface and an inner surface. The device also includes an inlet influid connection with the housing configured to receive a mixture of theparticles and the matrix, and a shaft within the housing with a lengthdefined between the inlet and an outlet. The shaft has a substantiallyconstant outer circumference and rotating about the center axis. Thedevice may further include a rupture portion of the shaft having surfaceinterruptions extending inwardly from the outer circumference, and anerosion portion of the shaft between the rupture portion of the shaftand the outlet. The erosion portion has a smooth outer surface along theouter circumference. Dispersion in the mixture occurs between the innerdiameter of the housing and along substantially an entirety of thelength of the shaft between the inlet and the outlet. Additionally, thedevice may include a screw groove along the outer circumference betweenthe inlet and rupture portion.

According to another an aspect of the disclosure, a device to orientparticles within a matrix, the device includes a moving plate adapted toreceive a mixture of the particles and the matrix, the moving platehaving an upper surface and an opposite bottom surface. The deviceincludes an angled stationary plate having a lower edge and a higheredge. A gap exists between the top surface of the upper surface of themoving plate and the lower edge of the angled stationary plate. The topsurface of the moving plate moves linearly from the higher edge of theangled stationary plate to the lower edge of the angled stationaryplate. The mixture disposed on the top surface of the moving plate isforced through the gap to orient the particles within the matrix.

BRIEF DESCRIPTION OF THE DRAWINGS

Illustrated embodiments of the disclosure are described in detail belowwith reference to the attached drawing figures, which are incorporatedby reference herein, and where:

FIG. 1A is a front perspective view of a machine in accordance with anillustrative embodiment;

FIG. 1B is a rear perspective view of a machine in accordance with anillustrative embodiment;

FIG. 2A is a side elevation view of a machine in accordance with anillustrative embodiment;

FIG. 2B is a side elevation view of a machine in accordance with anillustrative embodiment;

FIG. 3A is a front perspective view of a mixer in accordance with anillustrative embodiment;

FIG. 3B is a front perspective view of a mixer in accordance with anillustrative embodiment;

FIG. 3C is a front perspective view of a mixer in accordance with anillustrative embodiment;

FIG. 4 is a top plan view of a top portion of a stator in accordancewith an illustrative embodiment;

FIG. 4A is a cross-sectional view of the top portion of a stator of FIG.4 taken along section A-A;

FIG. 4B is a cross-sectional view of the top portion of a stator of FIG.4 taken along section B-B;

FIG. 4C is a cross-sectional view of the top portion of a stator of FIG.4 taken along section C-C;

FIG. 4D is a cross-sectional view of the top portion of a stator of FIG.4 taken along section D-D;

FIG. 5 is a top plan view of a middle portion of a stator in accordancewith an illustrative embodiment;

FIG. 5A is a cross-sectional view of the middle portion of a stator ofFIG. 5 taken along section A-A;

FIG. 5B is a cross-sectional view of the middle portion of a stator ofFIG. 5 taken along section B-B;

FIG. 5C is a detailed view of the middle portion of the stator of FIG.5B within section circle C;

FIG. 6 is a top plan view of a bottom portion of a stator in accordancewith an illustrative embodiment;

FIG. 6A is a cross-sectional view of the bottom portion of a stator ofFIG. 6 taken along section A-A;

FIG. 6B is a cross-sectional view of the bottom portion of a stator ofFIG. 6 taken along section B-B;

FIG. 6C is a cross-sectional view of the bottom portion of a stator ofFIG. 6B taken along section C-C;

FIG. 7 is a front elevation view of a shaft in accordance with anillustrative embodiment;

FIG. 7A is a cross-sectional view of the shaft of FIG. 7 taken alongsection A-A;

FIG. 7B is a detailed view of the shaft of FIG. 7 within section circleB;

FIG. 7C is a detailed view of the shaft of FIG. 7A within section circleC;

FIG. 8A is a front elevation view of a seal holder in accordance with anillustrative embodiment;

FIG. 8B is a cross-sectional view of the seal holder of FIG. 8 takenalong section B-B;

FIG. 9A is a front perspective view of a cooling channel modifier inaccordance with an illustrative embodiment;

FIG. 9B is a front elevation view of a cooling channel modifier inaccordance with an illustrative embodiment;

FIG. 9C is a cross-sectional view of the cooling channel modifier ofFIG. 9B taken along section C-C;

FIG. 9D is a detailed view of the cooling channel modifier of FIG. 9Awithin section circle D;

FIG. 10 is a bottom plan view of a moving plate in accordance with anillustrative embodiment;

FIG. 10A is a cross-sectional view of the moving plate of FIG. 10 takenalong section A-A.

FIG. 10B is a cross-sectional view of the moving plate of FIG. 10 takenalong section line B-B;

FIG. 10C is a front perspective view of a moving plate in accordancewith an illustrative embodiment;

FIG. 10D is a detailed view of a portion of the moving plate of FIG. 10Cwithin section circle D;

FIG. 10E is a detailed view of a portion of the moving plate of FIG. 10Awithin section circle E;

FIG. 10F is a detailed view of a portion of the moving plate of FIG. 10Awithin section circle F;

FIG. 11 is a top plan view of a stationary plate in accordance with anillustrative embodiment; and

FIG. 11A is a cross-sectional view of the stationary plate of FIG. 11taken along 10 section A-A.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIGS. 1A, 1B, 2A and 2B illustrate a high shear thin film machine 10 inaccordance with an exemplary embodiment of the present disclosure. Themachine 10 includes a frame 12 upon which the components of the machine10 are mounted. The present disclosure, however, contemplates that thecomponents may be installed on any suitable structure or surface toachieve the objects of the invention.

A motor 14 mounted on the frame 10 is operably connected to a mixer 16.A preferred embodiment includes a high horsepower electric motor, butthe present disclosure contemplates the motor 14 may be powered bypetrochemical, solar, stream, and the like. In the exemplary embodimentdepicted in FIG. 1, the motor 14 is connected to the mixer 16 through achain 18. The present disclosure envisions other means of connection,including belts, cables, gear box, and the like. In an alternateembodiment, the output shaft of the motor 14 may be coupled directly tothe mixer 16, thereby eliminating the need for a chain, belt, and thelike.

The mixer 16 may be secured to the frame 12 through any means commonlyknown in the art. For example, in the illustrated embodiment of FIGS.1A, 1B, 2A and 2B, a plurality of frame mounts 20 may connect with framemount holes 22 (FIG. 4A) within a top portion of the stator 26. Aplurality of connecting rods 28 may secure additional components of amotor column, including but not limited to, the coupler 30 and chainconnection 32.

Referring to FIGS. 3A-3C, the mixer 16 may be comprised of the stator 26and a shaft 34. The stator 26 may be comprised of the top portion 36, amiddle portion 38, and a bottom portion 40. The stator 26 may beconstructed from American Iron and Steel Institute (AISI) 1018 steel todecrease slippage between the boundary of the molten PNCs and shaft 34due to higher surface tension on the boundary. The present disclosurecontemplates other suitable materials, including but not limited to mildto low carbon steels and cold-rolled steels such as 304 stainless steeland 12L14 carbon steel.

The top portion 36, the middle portion 38, and the bottom portion 40 maybe connected through a bolt 42 that extends through the three portions,as shown illustratively in FIG. 3B. The bolt 42 extends throughcorresponding assembly holes 24 in each of the three portions. Further,the precise alignment of the top portion 36, the middle portion 38, andthe bottom portion 40 may be ensured through alignment pins 41 engagingalignment holes 43 in each of the three portions. While the illustratedembodiment shows a stator 26 comprised of three portions, the presentdisclosure contemplates that any number of portions may be implemented.For example, the stator 26 may be of unitary construction, particularlywith advances and/or refinement in the manufacturing processes used toconstruct the stator 26.

The top portion 36 of the stator 26 is shown illustratively in FIGS. 4A,4B, 4C and 4D. The top portion 36 includes an outer circumference 44, afirst inner circumference 46, and a second inner circumference 48. In anexemplary embodiment, the outer circumference 44, the first innercircumference 46, and the second inner circumference 48 are coaxial toone another, resulting in a cylinder with a tiered interior. The secondinner circumference 48 is sized and shaped to the outer surface of theshaft 34. The first inner circumference 46 is sized and shaped to theouter surface of a seal holder 94, which is discussed in detail below.

With a top surface 50 of the top portion 36 of the stator 26 is aplurality of axial mounting holes 52. The plurality of axial mountingholes 52 are adapted to connect the coupler 30 shown illustratively inFIGS. 1A, 1B, 2A and 2B. In an exemplary embodiment, the top portion 36has four axial mounting holes 52 disposed at twelve o'clock, threeo'clock, six o'clock and nine o'clock positions when the top portion 36of the stator 26 is viewed from above. However, the present disclosurecontemplates any number and/or arrangement of axial mounting holeswithout deviating from the objects of the present disclosure.

The top portion 36 of the stator 26 also has an inlet 54 for the polymerand/or nanoparticles. The location of the inlet 54 on the machine 10 isalso shown illustratively in FIGS. 1A and 2A. The inlet 54 is connectedto means for providing the polymer and/or nanoparticles. For example, inan exemplary embodiment, the inlet 54 is connected to a screw extruderthat provides the polymer-nanoparticle mixture. In an alternateembodiment, a second inlet (not shown) may be associated with the mixer16, wherein an inlet receives the polymer and the other inlet receivesthe nanoparticles. Further, the present disclosure contemplates that thepolymer and nanoparticles may be directly fed into the mixer of themachine 10 without the need of a screw extruder. Other means may includebut are not limited to pneumatics, hydraulics, and the like.

Referring to FIGS. 3B, 3C, 4C and 40, the stator 26 may contain one ormore cooling channels 56 disposed within the wall of the stator 26. Thecooling channels 56 address viscous dissipation heating due to the highviscosity of the nanocomposite melts. Each of the cooling channels 56 isassociated with a port 58. The port 58 may be an inlet port or an outletport. As shown illustratively in FIGS. 2A and 2B, each of ports 58connected to a coupler 64, which is connected to a tube (not shown)adapted to either supply or receive fluid. A pump (not shown) may pump afluid (e.g., coolant, water, air, etc.) through the couplers 64 into theports 58, after which the fluid travels down the cooling channels 56 tocool the receive the viscous dissipated heat within the wall of thestator 26. The cooling channels 56 extend from the top portion 36,through the middle portion 38, to the lower portion 40 of the stator 26.In the illustrated embodiment, the cooling channels 56 are comprised ofthree overlapping holes that effectively comprise a slot. The presentdisclosure contemplates cooling channels 56 of any size and shapewithout deviating from the objects of the present disclosure. Forexample, the cooling channels 56 may be of rectangular cross section toprovide for additional fluid flow. Further, each of the cooling channels56 may be threaded 66 to not only increase the heat transfer surfacearea of the channels 56, but also promote turbulence of the fluid withinthe channels 56. The threading 66 is illustrated in detail in FIGS. 5Band 5C.

Furthermore, each of the cooling channels 56 may receive a coolingchannel modifier 68, as shown illustratively in FIGS. 9A, 98, 9C and 90.The cooling channel modifier 68 may be sized and shaped to be insertedinto a cooling channel 56. The cooling channel modifier 68 is designedto increase the velocity of pumped fluid and further increase theturbulence of the same. In the illustrated embodiment, the coolingchannel modifier 68 has a rectangular cross section. The cooling channelmodifier 68 is comprised of a piece metal crimped at one end, asdetailed in FIG. 9D. The present disclosure contemplates any number ofcooling channel modifiers consistent with the objects of the presentdisclosure. For example, the cooling channel modifier 68 may becomprised of a threaded bolt-like structure to further increase surfaceheat and fluid turbulence. In another example, the cooling channelmodifier 68 may be a spring-like device to maximize the amount of fluidpumped while promoting fluid turbulence. In yet another example, thecooling channel modifier 68 may be formed integrally with the stator 26.

Referring to FIGS. 5, 5A and 58, the middle portion 38 of the stator 26may be comprised of an outer circumference 70 and an inner circumference72. The inner circumference 72 of the middle portion 38 corresponds tothe second inner circumference 48 of the top portion 36. As previouslydiscussed herein, the middle portion 38 may include alignment holes 43adapted to receive alignment pins 41, assembly holes 24 adapted toreceive assembly bolts 42, and cooling channels 56 adapted to receive acooling channel modifiers 68.

A lower portion 40 in accordance of an exemplary embodiment isillustrated in FIGS. 6, 6A, 6B and 6C. As previously discussed herein,the lower portion 40 may include alignment holes 43 adapted to receivealignment pins 41, assembly holes 24 adapted to receive assembly bolts42, and cooling channels 56 adapted to receive a cooling channelmodifiers 68. Further, the lower portion contains an outlet hole 74. Inan exemplary embodiment, the outlet hole 74 is eccentrically placed fromthe center of an inner circumference 76 of the lower portion 40. Thepresent disclosure, however, contemplates the outlet hole 74 may becentered as well. The outlet hole 74 may be associated with a funnelingchannel 78 that tapers from the inner circumference 76 to the outlethole 74. The funning channel 78 may be the frustum of a cone, as shownillustratively in the figures. The present invention contemplates othertypes of outlet holes 74, including but not limited to slits, coathanger dies, and the like, to promote a thin aspect ratio at the outlet.

Referring back to FIGS. 3A, 3B and 3C, the shaft 34 is disposed withinthe stator 26. An exemplary shaft 34 is illustrated in FIGS. 7, 7A, 78and 7C. The shaft 34 may contain a neck portion 80, a middle portion 82,and a main portion 84. The main portion 84 is sized and shaped to createa small gap with the second inner circumference 48 of the top portion36, the inner circumference 72 of the middle portion 38, and the innercircumference 76 of the lower portion 40. In a preferred embodiment, thegap is 0.1 millimeters. Thus, the present disclosure contemplates gapsof similar dimensions without deviating from the invention.

The main portion of the shaft 84 may contain a knurled region (orrupture region) 86 and a smooth region (or erosion region) 88. Theknurled region 86 is disposed proximate to the inlet 54 relative to thesmooth region 88. The knurled region 86 produces higher and more chaoticshearing forces to create aggressive mixing with higher flow rate. In apreferred embodiment, the knurled region 86 is approximately one-fourththe length of the main region 84 of the shaft 34. The rupture region 86was created shorter than the erosion region 88 because rupturing theagglomerations requires higher shear force and less time than erosion.In the erosion region, primary nanoparticle is continuously peeled apartfrom smaller aggregates in the erosion region, which requires more timeand less energy. As mentioned above, the gap between the erosion region88 and the stator 26 may be 0.1 millimeters. A gap between ruptureregion 86 and stator 26 may be a slightly smaller (e.g., approximately0.02 millimeters smaller). In addition, the knurled region 86 assists inincreasing the flow rate of the NPC within the mixer 16.

The main portion 84 of the shaft 34 may include a screw groove region90. The screw groove region 90 may be disposed adjacent to the knurledregion 86 opposite the smooth region 88. The screw groove region 90 mayfurther be disposed proximate to the inlet 54 relative to the knurledregion 86. The screw groove region 90 assists in moving thepolymer-nanoparticle mixture downwardly into the mixture (i.e., towardsthe knurled region 86). In an exemplary embodiment gap between shaft 34and stator 26 in this screw groove region 90 may be a slightly smaller(e.g., approximately 0.03 millimeters smaller) than the rupture region.

The middle portion 82 of the shaft 34 may be operable connected to aseal 92 and seal holder 94, as shown illustratively in FIGS. 3A and 3C.The seal 92 is required to withstand the demands of the application. Inparticular, the application may have temperatures exceeding 230° C. andpressures of approximately one thousand kilopascals. In a preferredembodiment, the seal 92 may be an O-ring comprised ofpolytetrafluoroethylene (PTFE). The present disclosure contemplatesother seals comprised of Kalrez perfluoroelastomer, spring-loaded singlelips, and the like.

An exemplary seal holder 94 is illustrated in FIGS. 8A and 8B. The sealholder 94 may include a first outer circumference 96 sized to fit withinthe first inner circumference 46 of the top portion 38 of the stator 26,and a second outer circumference 98 sized to fit within the second innercircumference 48 of the top portion 38 of the stator 26. The seal holder94 may further include a first inner portion 100 sized to accommodatethe middle portion 82 of the shaft 34, a second inner portion 102 sizedto accommodate the seal 92, and a third inner portion 104 sized toaccommodate a portion of the neck 80 of the shaft 34. In an exemplaryembodiment, the seal holder 94 may be constructed from AISI 1018 steelbut the present disclosure contemplates other suitable materials,including but not limited to mild to low carbon steels and cold-rolledsteels such as 304 stainless steel and 12L14 carbon steel. Referringback to FIGS. 3A, 3B and 3C, one or more ball bearings 106 may bedisposed within the top portion 38 of the stator 26 adjacent to andabove the seal holder 94. The one or more ball bearings 106 provideradial stability to the neck 80 of the shaft 34. Further, one or moreneedle bearings 108 may be disposed within the top portion 38 of thestator 26 adjacent to and above the one or more balling bearings 106.The one or more needle bearings 108 provide axial stability to the shaft34. Still further, a snap ring 110 may be configured to secure to aridge 112 on the neck 80 of the shaft 34. Still yet further, an axialridge 114 proximate to an end of the shaft 34 is configured to engage tothe means for powering the mixer 16.

In operation, a polymer nanoparticle (NPC) mixture (or separately) arefed into the inlet 54 of the stator 26. The motor 14 provides arotational force to the shaft 34 via the interface at the axial ridge114. The shaft 34 rotates at a high frequency. In an exemplaryembodiment, the shaft 34 rotates at a frequency of 17,800 Hertz. The NPCmixture encounters the screw groove region 90 of the shaft 34, whichforces the NPC mixture towards the knurled region 86. In the knurledregion 86, the agglomerations within NPC mixture experienceextraordinary shearing forces that rupture the same. Due to forces fromNPC mixture present in the screw groove region 90 above, the NPC mixtureis further forced down into the smooth region 88. The NPC mixtureundergoes extremely efficient erosion, whereby the NPC mixture becomeshighly exfoliated. Thereafter, the NPC mixture is discharged from theoutlet 74 of the stator 26 and to the orienter, which is discussed indetail below.

While in operation, fluid is pumped from a reservoir through couplers 64and into the ports 58 of the top portion 36 of the stator 26. The fluidenters the cooling channels 56, wherein it encounters threading 66 andthe cooling channel modifier 68. The fluid experiences heat transfer dueto the increased surface area and turbulent now, thereby cooling thestator 26.

The present disclosure also contemplate that the mixer 16 can used as acontinuous heterogenic catalyst reactor, if shaft outside surface andthe stator inside surface are coated with catalyst. In such anembodiment, the catalyst will not be fouled due to self-cleaning by thehigh shear stress.

When the dispersed and exfoliated NPC mixture exits the outlet 74 of thestator 26, the mixture enters the orienter 120. Orientation does notrequire the high energy necessary for dispersion. In order to orientHARNPs within a polymer matrix requires fully developed steady laminarshear flow (FDSLSF). However, 10 get the FDSLSF is complicated due tosurface roughness at the nanoscale. The orienter 120 of the presentdisclosure achieves FDSLSF by moving a moving plate 122 across astationary plate 124 at a slight angle 121. In particular, the NPCmixture is disposed on a top surface 126 of the moving plate 122, afterwhich the moving plate 122 travels at a slight angle 121 across thestationary plate 126 to orient the NPC based on the combination ofshearing and extensional two-dimensional, drag-force-driven flow.

An exemplary embodiment of the orienter 120 is illustrated in FIGS. 1A,1B, 2A and 2C. The orienter 120 is comprised of a track 128 mounted onthe frame 12. The track 128 is configured to movably connect to fivemoving plates 122. The orienter 120 may further include a motor 130connected to a drive gear 132. The drive gear 132 is configured tomovably be coupled to teeth 134 on a lower surface 136 of the movingplate 122. Referring to FIGS. 10, 10A, 10B and 10C, a moving plate of anexemplary embodiment is illustrated. The moving plate 122 may becomprised of the upper surface 126 and the lower surface 136. One ormore rows of the teeth 134 may be connected to the lower surface 136 ofthe moving plate 122. The moving plate 122 may be constructed ofaluminum or any other metal commonly known in the art without deviatingfrom the objects of the present disclosure.

The stationary plate 124 is mounted on the frame 12. As illustrated inFIGS. 11 and 11A, the stationary plate 124 one or more arms 138 that arerigidly connected to the frame 12. The stationary plate 124 furthercomprises a lower surface 140. The stationary plate 124 may beconstructed of aluminum or any other metal commonly known in the artwithout deviating from the objects of the present disclosure.

The inlet side distance between the moving plate 122 and stationaryplate 124 may be 0.24 mm while the outlet side distance may be 0.1 mm.Further, the moving plate 122 may decline at approximately athree-degree angle 121 relative to horizontal, or may be parallel.

The orienter 120 is in concurrent operation with the mixer 16 of themachine 10. In operation, the orienter 120 may receive a dispersed andexfoliated NPC mixture from mixer 16. The NPC mixture may descend ontothe top surface 126 of the moving plate 122 through the force ofgravity. The motor 130 drives the drive gear 132 that forces the movingplate 122 across the stationary plate 124, thereby exposing the NPCmixture to FDSLSF and/or to two-dimensional extending drag flow, therebyorienting the nanoparticles with the polymer mixture.

In the illustrated embodiment, the cycling process of the moving plates122 is not automated; i.e., an individual must manually remove themoving plate 122 from an end of the track 128 and replace it at abeginning of the track 128. The present disclosure envisions a fullyautomated system.

Further, the moving plates lose heat during the continuous cycle. Themoving plates need to cycle in closed area to prevent loose heat. Thepresent disclosure envisions an enclosure that minimizes heat loss ofthe orienter 120.

The resulting NPC is dispersed, exfoliated, and oriented. The examplesof improved physical properties (and other testing results) arediscussed in Appendix A, which is incorporated herein by reference inits entirety.

The disclosure is not to be limited to the particular embodimentsdescribed herein. In particular, the disclosure contemplates numerousvariations in the type of ways in which embodiments of the disclosuremay be applied to disperse, exfoliate and orient high aspectnanoparticles with a polymer matrix. Further, the present disclosurecontemplates that the mixer 16 and the orienter 120 of the HSTFM may beutilized separately as an independent mixer and orienter. The foregoingdescription has been presented for purposes of illustration anddescription. It is not intended to be an exhaustive list or limit any ofthe disclosure to the precise forms disclosed. It is contemplated thatother alternatives or exemplary aspects that are considered included inthe disclosure. The description is merely examples of embodiments,processes or methods of the disclosure. It is understood that any othermodifications, substitutions, and/or additions may be made, which arewithin the intended spirit and scope of the disclosure. For theforegoing, it may be seen that the disclosure accomplishes at least allthat is intended.

The previous detailed description is of a small number of embodimentsfor implementing the disclosure and is not intended to be limiting inscope. The following to claims set forth a number of the embodiments ofthe disclosure with greater particularity.

What is claimed is:
 1. A method to disperse and orient nanoparticleswithin a matrix, the method comprising: providing a mixer having astator and a shaft; providing an orienter having a stationary plate anda moving plate; feeding the nanoparticles and the matrix into the mixer;applying a rotational force to the shaft, wherein shearing forcesdisperse the nanoparticles within the matrix; exposing the nanoparticlesand the matrix to an erosion region of the shaft having a substantiallysmooth surface; outputting a dispersed mixture onto the moving plate;and moving the moving plate, horizontally along a track, across thestationary plate, wherein the dispersed mixture is pressed between themoving plate and the stationary plate, and wherein the distance betweenthe moving plate and the stationary plate decreases as the moving platemoves past the stationary plate; and orienting the dispersed mixturewith a laminar shear flow or a two-dimensional extensional drag flow. 2.The method of claim 1, further comprising: exposing the nanoparticlesand the matrix to a rupture region of the shaft having surfaceirregularities.
 3. The method of claim 1, wherein the moving plate iscoincident with a first horizontal plane and the stationary plate isangled relative to a second horizontal plane parallel and proximate tothe first horizontal plane.
 4. The method of claim 1, furthercomprising: pumping a fluid through one or more cooling channels withinthe stator of the mixer.
 5. The method of claim 4, further comprising:inserting an elongated member within the one or more cooling channels toincrease gas velocity passing through the one or more cooling channels.6. The method of claim 4, further comprising: providing threading on asurface of the one or more cooling channels to increase surface area ofthe surface of the one or more cooling channels for dissipating heat. 7.The method of claim 1, further comprising: inserting a volume modifierinto one or more cooling channels within the stator of the mixer toincrease velocity and still maintain constant flow rates.